In manufacturing "niche" or low volume vehicles, setup costs and down time must be minimized in order to enable operations to be conducted efficiently. As used herein "low volume" refers to production volumes of less than about 30,000 units per year. Especially in such operations, it is desirable to reduce the number of processing steps. Ideally, the manufacturing engineer would wish to eliminate tooling which is part-specific, so that once mounted, a given tooling could be used to shape more than one part. Such manufacturing objectives rise in significance when one contemplates entry into a new vehicle market with a minimum initial investment.
Generally, as used herein the term "press" connotes an apparatus having a stationary bed or a rolling bolster and a slide or ram that has reciprocating motion at right angles, or parallel to, or inclined to the bed surface, the slide being guided in the frame of the apparatus. A "die" connotes a tool, often containing a cavity, that imparts shape to a solid metal or plastic primarily because of the shape of the tool itself. A die is typically used in such press operations as blanking, drawing, forging, and forming. As used herein, "bolster" refers to a plate to which dies or tools may be fastened, the assembly being secured to the top surface of a press bed.
In manufacturing operations which utilize a press and a die assembly, the die is typically part-specific. When a part having a different shape is to be formed, the die must be replaced or reoriented. Thus, the manufacturing cycle ccnventionally includes a series of steps within which a die is changed in order to form a specific part. Such steps functionally differ from those involved in the press cycle. In the press cycle, various steps are followed in order to shape a given part from the die components which have been selected.
In related prior art is U.S. Pat. No. 5,216,913 which discloses an improved bending machine for wire- or strip-shaped material. The '913 reference discloses a working plate disposed in a vertical position on a machine frame. U.S. Pat. No. 3,802,246 discloses a multiple motion press for fabricating sheet metal, including a lateral reciprocating ram which is slidably mounted on the press frame. U.S. Pat. No. 3,561,248 discloses a bumper forming apparatus including a pair of longitudinally shaped moveable male die members adapted to move toward and away from each other. Also illustrative as references disclosing bending presses for sheet materials are U.S. Pat. Nos. 4,753,099 and 5,253,502.
A die assembly used within a single stage forming operation is disclosed in our U.S. Pat. No. 5,465,600, which is incorporated herein by reference.